The invention to which this application relates is apparatus and a method for erecting a packaging sleeve from a blank, folded substantially flat condition to an in-use condition for subsequent insertion of an article, most typically a tray, therein to form a package.
Reference hereonin is made to the insertion of an article in the form of a tray but this reference does not limit the invention for use solely with a tray. In addition reference to a sleeve incorporates many different designs of sleeve, examples of which are provided herein in a non-limiting manner.
Particularly, although not necessarily exclusively, the sleeve is what is known as a 5-fold sleeve formed from card and having a top face, bottom face, and two opposed side walls joining said top and bottom faces and with one of the side walls having an intermediate elongate fold line. The sleeve, when erected, defines a passage with an opening at each end thereof into which a tray can be inserted. Typically, two of the fold lines define the corners between the front face and side walls, two fold lines define the corners between the side walls and the bottom face, with the fifth fold line located intermediate the corner fold lines of one of the side walls. When provided in the folded or blank condition as referred to herein, the free ends of the sleeve are already joined together, typically by gluing, in an overlapping manner, said join typically but not always, positioned at or adjacent one of the side walls.
Typically, the packages are provided as retail packs, provided to hold a foodstuff such as a frozen or chilled foodstuff for purchase in a retail outlet and subsequently, by removal of the sleeve, and typically an enclosing film, the foodstuff can be eaten or first cooked in the tray at home.
Large numbers of said packages are sold on a daily basis and conventionally the packages are formed manually or automatically using appropriate machinery. In each case there is a significant problem in terms of the relatively slow throughput of the packages due to the package forming process and apparatus, if any. If a manual process is used, the sleeve is moved from a blank to an erected form by hand and the tray inserted into the sleeve passage through one of the openings. In an automatic process the sleeve is moved from a blank to an erected form by the provision of mechanical fingers which locate on the bottom face of the blank and pull the same downwards and away from the top face and so move the sleeve into a former into which the tray can then be inserted either manually or by automatic pushers. In one embodiment, the fingers include suction means such as vacuum pads to locate and move the sleeve.
Thus, if the process is performed manually, the same is intensive in terms of personnel and, if performed automatically, the process is slow due to the fact that no continuous forming operation occurs. Other automated package forming apparatus is known but tends to relate to the erection of boxes from blanks rather than sleeve blanks and, as such, is not applicable or usable in practical terms as is evidenced by the conventional apparatus and methods currently used for sleeves. One box blank erecting apparatus is disclosed in U.S. Pat. No. 2,900,880 where a box with right angled side faces with respect to the front and bottom faces is formed.